Abstract:
The trust data is critical to the trust model of P2P system. In this paper we present an efficient certificateless cryptography scheme and propose a protocol which provides the ability for sharing trust data securely. The protocol avoids the escrow problem identity-based cryptosystem and the secure delivery of private keys. The security of scheme is based on some underlying problems closely related to the Bilinear Diffie-Hellman Problem are computationally hard. It tolerates the Type I and Type II adversary. The proof of security is presented in the random oracle model. Through security discussion, we show that my secure protocol is extremely secure when encounter a variety of possible attacks.

Abstract:
Let C be a nonempty closed convex subset of a real Banach space X which has a uniformly Gâteaux differentiable norm. Let T∈ΓC and f∈ΠC. Assume that {xt} converges strongly to a fixed point z of T as t→0, where xt is the unique element of C which satisfies xt=tf(xt)

Abstract:
Real-time rapid prediction of variations of the Earth’s rotational rate is of great scientific and practical importance. However, due to the complicated time-variable characteristics of variations of the Earth’s rotational rate (i.e., length of day, LOD), it is usually difficult to obtain satisfactory predictions by conventional linear time series analysis methods. This study employs the nonlinear artificial neural networks (ANN) to predict the LOD variations. The topology of the ANN model is determined by minimizing the root mean square errors (RMSE) of the predictions. Considering the close relationships between the LOD variations and the atmospheric circulation movement, the operational prediction series of axial atmospheric angular momentum (AAM) is incorporated into the ANN model as an additional input in the real-time rapid prediction of LOD variations with 1–5 days ahead. The results show that the LOD prediction is significantly improved after introducing the operational prediction series of AAM into the ANN model.

Abstract:
These results elucidate from a new point of view, that the excitations from AAM, OAM, and HAM are the main sources of the Chandler wobble, and the Chandler wobble excitation function is of a random normal property.

Abstract:
Using the length-of-day (LOD) data series derived from astronomical observations made by various modern space techniques, southern oscillation index (SOI) and anomalies of sea surface temperature (SST) in tropical Pacific Ocean, the inter-annual components of these data series are obtained by the technique of band filtering from January 1962 to October 2002. It is found that a new ENSO event has already occurred in 2002 and been detected by the interannual LOD. It is shown by the wavelet analysis that the component with a period of about 4–6 years and the quasi-biennial component are out of phase during 2001–2002, which consequently suggests that the new ENSO event cannot be a strong one.

Abstract:
Real-time rapid prediction of variations of the Earth's rotational rate is of great scientific and practical importance. However, due to the complicated time-variable characteristics of variations of the Earth's rotational rate (i.e., length of day, LOD), it is usually difficult to obtain satisfactory predictions by con-ventional linear time series analysis methods. This study employs the nonlinear artificial neural net-works (ANN) to predict the LOD variations. The topology of the ANN model is determined by minimizing the root mean square errors (RMSE) of the predictions. Considering the close relationships between the LOD variations and the atmospheric circulation movement, the operational prediction series of axial atmospheric angular momentum (AAM) is incorporated into the ANN model as an additional input in the real-time rapid prediction of LOD variations with 1-5 days ahead. The results show that the LOD pre-diction is significantly improved after introducing the operational prediction series of AAM into the ANN model.

Abstract:
A new algorithm for efficient key management for secure group communication in P2P network is presented. The protocol avoids the escrow problem in identity-based cryptosystem and the secure delivery of private keys. It has two rounds and requires constant pairing operation per user. The security of protocol is based on some underlying problems closely related to the Bilinear Diffie-Hellman Problem are computationally hard.

Abstract:
One way to minimize threats in P2P system is to exploit reputation to help evaluate the trustworthiness and predict the future behaviors of peers. In this paper, a set of parameters are identified for describing the trust of a peer. And a trust model based on fuzzy techniques is presented. The trust model uses Amplifier of Malicious Behavior (AMB) to intensify malicious behaviors and helps peers identify the sly malicious peers. The recommendation credibility is evaluated by Recommendation Weight (RW) and Recommendation Accuracy (RA). In simulation, this trust model has been shown to improve the efficiency of P2P system by significantly decreasing the number of inauthentic files on the network.

Abstract:
We introduce an iteration scheme for nonexpansive mappings in a Hilbert space and prove that the iteration converges strongly to common fixed points of the mappings without commutativity assumption.